Noodle processing, storage time and cooking affect the antioxidant activities and phenolic compounds content of Qingke barley noodles.

Summary: The impact of noodle processing, storage and cooking on the total phenol content (TPC) and total flavonoid content (TFC) was assessed. Total phenol content (TPC) and total flavonoid content (TFC) of mixed flour were 77.50 and 39.56 mg per 100 g, respectively, and it decreased to 71.80 and 36.30 mg per 100 g after noodle processing. For the fresh Qingke barley noodles (FQBNs), stored at 25 °C, both TPC and TFC decreased significantly during storage. After cooking the fresh noodles, the TPC of the noodles stored for 0 and 4 h increased, while it decreased for the noodles stored for 8, 16 and 24 h; the TFC of all cooked Qingke barley noodles (CQBNs) decreased. Compared with the flour, the DPPH•, ABTS•+, HO• and O2∙- scavenging ability and ferric reducing antioxidant power (FRAP) decreased significantly (P < 0.05) after noodle processing. For FQBN, increased storage time led to a reduction in antioxidant ability. After cooking, the DPPH• and HO• scavenging ability and FRAP of noodles stored at 25 °C for 0 and 4 h, and the ABTS•+ and O2∙- scavenging ability of noodles stored at 25 °C for 0, 4 and 8 h increased. Overall, noodle processing, storage and cooking will affect the phenolic compound content and antioxidant activities of barley noodles. Although the shelf life of FQBN is 17 h at 25 °C, from the perspective of nutrition, it is not suitable for long‐term storage, and it is best choice to consume it within the first 4 h. [ABSTRACT FROM AUTHOR]